wanting to learn how to properly I.D. apistogramma

[ErtyJr]

Temperature varies widely in apisto biotopes, depending on season, time of day, etc. Still, apistos can pick a preferred temp by moving up and down in the water. Temperatures vary by several degrees in just a short depth difference in most places.

You know that's something I knew, from being an avid fisherman, and just did even apply it to my fish keeping knowledge. Very good thing to keep on mind. I think when I remove my fry and female in the next few weeks I will drop the temp down a bit to 76 or so. Or perhaps lower? What do you guys think?

I've always had it in my head that tropical fish would not enjoy being so low like 70. Seems so low to me.

 

[Mike Wise]

Don't drop the temp during the frys' first 2 months. By that time the sex ratio should be fixed. Lower temperatures will slow the growth of the fry, but otherwise should be OK.

 

[rr16]

Disclaimer: That might not apply to ALL Apistos. There might be some species that really do need high 70s-low80s all the time. Would sure be nice to know the annual range of stream temperatures in each local region or river, not just the temp when some fish collector happened to be there.

I mentioned the same thing (as well as hardness, conductivity, water flowrates/speed and pH) in a conversation with Tom C recently. Anyone want to fund me to go out there and study the conditions on let's say 3 or 4 times per year?

 

[ErtyJr]

Don't drop the temp during the frys' first 2 months. By that time the sex ratio should be fixed. Lower temperatures will slow the growth of the fry, but otherwise should be OK.

Ah, I believe my post was not 100% clear. I was planning on dropping the temp on the community tank, the tank the fry are in will remain at 79-80 untill they have been sold.

Just something that occurred to me. If the fry sex is determined, in part, by temp in the first 2 months, then after the second month, assuming that heat speeds up the metabolism, could I not crank up the heat to like 86 and increase feedings and they would grow faster?

 

[Mike Wise]

True, raising the temperature will increase their metabolism and they may grow larger faster but they age faster, too. Cold blooded animals have upper and lower temperature lethal limits. If you get too close to either limit you will see the animal start to 'shut down'.